The human spine is a main structural support for the body, as well as a conduit for nerve bundles that communicate with the brain. The spine comprises bony masses called vertebra that are linked by flexible tissue, separated by flexible intervertebral discs, and structurally joined by ligaments. A healthy human spine (see the description for FIG. 1 below) possesses curvatures along the sagittal plane: forward leaning curves called lordotic curves in the cervical and lumbar regions, and a rear-leaning curve in the thoracic region called kyphosis. These curvatures are essential for balance, freedom of movement, pain-free living, and healthy circulation of bodily fluids in and around the spine.
Persons with improper, flattened, or reversed lordotic and kyphotic curves, whether due to injury, neglect, or pathology tend to suffer from decreased natural joint movement and also decreased or non-existent fluid transfer around the spinal region, such as decreased circulation throughout the canaliculi or microscopic passages in bone tissue, as well as decreased overall blood circulation. This can be problematic because active transport is needed to prevent degradation of the spinal discs. Also, the mechanical penalty for flat or reversed lordotic curves is that the intervertebral discs also degenerate from the load imposed by the head and during movements like walking and jumping. So when needed, the restoration of healthy lordotic curves, such as by judicious imposition of force therapies, can be extremely important for health and longevity.
Spinal traction and restoration devices have been proven successful in many cases in relieving pain, pressure and inflammation in the cervical and lumbar spine as well as restoring the cervical and lumbar lordosis (forward curve), to great therapeutic benefit. This has been particularly valuable for treatment after injuries and accidents, where a sudden movement of the head or neck, along with whiplash or rebound, causes injury to surrounding and supporting tissues of the neck and head, including injury to the intervertebral joints, discs, ligaments, muscles, nerve roots and blood vessels.
Prior art traction devices have typically used solid neck supports, weights, chin restraining straps and a single, fixed position of tractional force. These devices are said to be uncomfortable, and can cause an undue amount of stress. It is also not possible in the prior art to direct the tractional force specifically to the area of maximum therapeutic effect.
Much of the prior art is devoted to the mechanical imposition of a form (or the equivalent) upon the spine to induce healthy lordosis. U.S. Pat. No. 5,382,226 to Graham discloses an inflatable cervical traction and exercising device which imposes a somewhat spherical form onto the cervical spine in an effort to produce normal lordosis, as discussed below. The device of Graham '226 uses an unconstrained bladder which tends to be non-differentiating, and amounts to merely pushing a spherical body onto the cervical spine. The device of Graham '226 cannot provide true or direct longitudinal traction, or targeted force for therapeutic benefit.
The spinal therapy machine of U.S. Pat. No. 6,652,564 to Harris et al. describes a constraint running around the sides and ends of an inflatable bladder, but the bladder is not capable of producing pointable, direction-selective force, and no specific action on specific vertebra is taught or suggested. Therapeutic actions are taken generally on the cervical and/or lumbar spine, but no specific teaching is given for adjusting significantly the direction of force applied thereon.